Posts Tagged ‘reclaim lost RAM’

Understanding “vmalloc region overlap”

Tuesday, August 16th, 2011

I recently came across the following disconcerting message in my kernel’s boot output:

Truncating RAM at 40000000-5fffffff to -57ffffff (vmalloc region overlap).
...
Kernel command line: console=ttySC0,115200 mem=512M
...
Memory: 384MB = 384MB total

Which is the kernel’s way of saying “I understand there may be some RAM here – but I’m not going to use it all”. So what is the cause of this warning? And what do we need to do to reclaim that lost RAM?

(more…)